Normal but shouldn't be, Benz redesigned the charging system in 1990 & added an extra 15amps of power in the alternator! Most 1986-89 300E's suffer with this & other problems due to this. AT dealer where I work we always try to inform customers(who already need replacment) that for $50-60 more they can install the 80 amp alternator.

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MERCEDES Benz Master Guild Technician (6 TIMES)
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